INDUSTRIAL-TYPE MOBILE ELECTRIC SOCKET AND PLUG OF EASIER ASSEMBLING

Abstract: A socket or plug of easier assembly consisting in a fruit (1) and a handle (2) axially restrained by means of a pair of inclined planes is provided with a projection (6), positioned on one of the two parts (1, 2), whose inner surface (5) is shaped so as to engage a shaped resilient member (3) housed in a seat (4), formed in the other of the two parts (1, 2), so that it blocks the rotation of the two parts (1, 2) leaving uncovered a portion of said resilient member (3) wide enough to exert thereon a pressure sufficient to disengage the member (3) from the projection (6).

Description: "INDUSTRIAL-TYPE MOBILE ELECTRIC SOCKET AND PLUG OF EASIER ASSEMBLING" The present invention concerns mobile electric sockets and plugs of industrial type and in particular a socket and a plug of easier assembling. As it is known, many electric apparatuses are used both in the industrial field in general and in the handicraft and services fields requiring a connection to the electrical network or one to the other through mobile, i.e. not wall-fixed, plugs and sockets. The safety regulations for these product are increasingly strict and in particular the latest IEC regulation concerning this matter (309-1-2) requires that the mobile plugs and sockets are made in such a way as to necessarily require a tool to disassemble them. The Applicant has already filed an application for utility model n.MI93U000406 wherein a mobile plug and socket meeting the requirements of said regulation are disclosed. The plugs and sockets essentially consist, as described in said application, in a first part, called "handle", and a second part, called "fruit", which is mounted on the handle. Reference will be made in the following to a socket, being clear that what will be said can be applied to a plug too. In the sockets of the prior art, the mounting of the fruit on the handle is usually carried out by means of a pair of screws, so as to satisfy the above-cited IEC 309-1-2 regulation since it is not possible to disassemble the socket with the bare hands but a screwdriver is required. However, this solution has the serious drawback that also the mounting obviously requires the use of the screwdriver and therefore a certain waste of time. Since these mobile sockets and plugs are mounted in thousands on any kind of electric tool and the like (drills, welders, etc.) to be used in the environments considered in the relevant plant regulations, a substantial waste of time results therefrom with a consequent increase in the labour cost for the assembly of the plugs and sockets. The above-cited application n.MI93U000406 discloses a socket overcoming said drawback by means of two shaped profiles, formed on the facing surfaces of two projections located in the frontal area of the coupling abutments, suitable to be mutually engaged so as to block the rotation between the fruit and the handle leaving therebetween a cavity wherein a tool is to be inserted to disengage said profiles. This solution, though effective, has the drawback that the tool directly acts on the shaped profiles, usually made of plastic, and can thus cause a deformation which may result permanent, especially in case of repeated disassembling. Therefore, the object of the present invention is to provide a socket which can be easily assembled with no need to use tools or additional fastening elements such as screws, yet it can satisfy the above-cited IEC 309-1-2 regulation and has no problems of deterioration of the blocking members even in case of repeated disassembling. This object is achieved by means of a socket having the characteristics cited in claim 1. This socket has therefore the advantage of allowing a significant reduction in the time, and thus the cost, required for the mounting of the fruit on the handle. A further advantage, with respect to the socket disclosed in the above-cited application, is given by its capability of repeated disassembling without any deterioration of the blocking elements. These and other advantages and characteristics of the device according to the present invention will be apparent from the following detailed description of a preferred embodiment thereof, reported as a non- limiting example, referring to the annexed drawings wherein: Fiα.1 is a perspective exploded view of the members making up the socket according to the present invention; Fiα.2 is a perspective view of the three parts of the preceding figure assembled but not yet blocked; and Fiα.3 is a perspective view of the socket of fig.2 in the blocked position. Referring to fig.1 , there is seen that a mobile socket according to the present invention consists in a fruit 1 mounted on a handle 2 by means of a pair of inclined planes which cover a limited arc of the socket periphery, as described in the above-cited application n.MI93U000406. The mounting is carried out in the same way as already described in said application and therefore will not be described here in detail. The socket according to the present invention can satisfy the above- cited regulation thanks to a device for blocking fruit 1 on handle 2 consisting in a resilient member 3 inserted in a seat 4 and shaped so as to engage a corresponding shaped inner surface 5 of a projection 6. In the illustrated embodiment seat 4 is formed below abutment 7 of handle 2, while projection 6 is positioned below abutment 8 of fruit 1. Clearly, this arrangement could be inverted by forming seat 4 above abutment 8 and by positioning projection 6 above abutment 7. As more clearly shown in fig.2, the profile of surface 5 includes an inclined plane 9 ending, at the end towards the direction of mounting, with a plane 10 followed by another short plane 11 , orthogonal to said plane 10 and substantially parallel to the socket axis. Similarly, the outer profile of the resilient member 3 includes an inclined plane 12, substantially equal to plane 9, ending, at the end towards the direction of mounting, with a short plane 13, substantially parallel to plane 11 , followed by a further plane 14 almost orthogonal to said plane 13. Plane 12 is connected at the other end with a lower plane 15 (fig.1 ) which abuts on the bottom of seat 4. Since member 3 is made of a resiliency bendable material, preferably spring steel, the above-described shape allows it to be pushed so that the upper portion made up of planes 12, 13 and 14 gets near to the lower plane 15 by resilient deformation of the curved radius 16 included between planes 12 and 15. Referring finally to fig.3, there is seen that, by performing a leftwards rotation of fruit 1 from the position of fig.2, projection 6 engages member 3 so as to block the rotation of the two parts of the socket. In particular, the tooth formed by plane 13 is engaged by the abutment formed by plane 11 , and projection 6 leaves partially uncovered plane 14 which comes to be below the edge of seat 4. The tooth can be disengaged from the abutment by pushing on the uncovered portion of plane 14 with a screwdriver, or a similar tool, thus allowing the socket disassembling. It is clear that the above-described and illustrated embodiment is just an example of the shapes of member 3 and projection 6 which make up the blocking device, being obvious that the same kind of device may be realized with numberless variations of the profile used in the present invention, and the kind of axial restraint between fruit 1 and handle 2 may be different as well, for example a screw thread instead of inclined planes, as far as it remains of a kind requiring a rotation between the parts for the disassembly.

Claims: CLAIMS 1. A mobile electric socket or plug of industrial type consisting in a fruit (1) and a handle (2) axially restrained by means of a pair of inclined planes or the like, characterized in that it is provided with a projection (6) positioned on one of the two parts (1 , 2) of the socket or plug, whose inner surface (5) is shaped so as to engage a shaped resilient member (3) housed in a seat (4), formed in the other of the two parts (1, 2) of the socket or plug, so that it blocks the rotation of the two parts (1, 2) leaving uncovered a portion of said resilient member (3) wide enough to exert thereon a pressure sufficient to disengage the member (3) from the projection (6). 2. A socket or plug according to claim 1 , characterized in that the seat (4) and the projection (6) are both located below or above the abutments (7, 8) between the two parts (1 , 2). 3. A socket or plug according to claim 1 or 2, characterized in that the shaped profiles of the member (3) and of the surface (5) consist in a series of straight segments (9, 10, 11, 12, 13, 14) defining an abutment and a tooth complementary thereto. 4. A socket or plug according to any of the claims from 1 to 3, characterized in that the resilient member (3) is made of spring steel.

Inventors: MAPELLI GIOVANNI, MAPELLI, GIOVANNI
Applicants: MAPELLI GIOVANNI, SCAME PARRE S P A, MAPELLI, GIOVANNI, SCAME PARRE S.P.A.
Application year: 1994
Main classification: H01R13
IPC codes: H01R13